The present invention relates generally to an apparatus for controlling attitude of a road vehicle cab and, more particularly, to a hydraulic suspension mechanism for maintaining a stable cab orientation with respect to a road surface.
A hydraulic suspension system for controlling vehicle cab attitude is disclosed in Japanese Publication No. 163683/1994. However, the disclosed system merely controls three freedoms of cab movement, i.e. rolling, pitching and vertical movements. Consequently, the disclosed system fails to reduce riding discomfort caused by the lateral or longitudinal vibration of a cab.
The object of the present invention, therefore, is to provide a system which can reduce both reciprocating and rotational vibrations of a vehicle cable so as to improve riding comfort.